Ryan Horsley has it here at Red's Trading Post.
I recall the 2001 Area 1 USPSA Tournament in Washington, which I attended with an STI Edge which I received from my then gunsmith AT THE MATCH. I had given it to him to perform some minor maintenance, including a thorough cleaning. He had completely disassembled the pistol, cleaned and lubricated everything ... but I had neglected to give him the magazines and some ammunition to test it. Since the pistol is in 10mm, which nobody except for The Geek used for Practical Shooting competition, he had been unable to test the re-assembled pistol.
The first time I shot it was in Stage 1 of the match, at which the pistol doubled (fired multiple shots when the trigger was pulled.) I was ejected from the stage, given a zero score, and my gunsmith and I spent the next 40 minutes at a safety table ... where we discovered that he had inserted the sear spring ('3-finger spring') incorrectly.
He put it together again, this time correctly, and we visited the Function-Test bay a couple of times until we were sure it was right.
In the actual event, the Match Director discovered that my score sheet for Stage 1 had been filled out wrong .. among other things, I had never signed it and they hadn't entered the time or the score (zero), so I was required to reshoot the stage. As usual, I didn't impress anyone, but my stage score was a lot better than ZERO so I was happy, all things considered.
Here's the down side:
Under the new BATFE ruling, the fact that my pistol actually shot more than one round with a single trigger-pull, ATF considers it a machine gun. There are no accommodations for malfunctions.
There are several malfunctions which can cause a semi-automatic pistol to 'double', including a worn sear ... which may be caused by poor maintenance, an overly enthusiastic trigger job, or normal wear on a firearm which has been used so much that he metal on the sear face erodes. (I've had that happen when a relatively new sear was found to have suffered from a 'manufacturing defect', and the manufacturer cheerfully replaced the deficient part with abject apologies.)
And again, if a sear spring is incorrectly installed, the pistol will double even though that is not the design intent.
Consider this scenario:
You're at a USPSA match, you're your own gunsmith, and you put the gun together 'wrong' after a detail cleaning. You start to shoot the stage, and your gun doubles. This is an 'unsafe firearm' according to USPSA rules, and you are required to (a) stop shooting immediately, and (b) not continue shooting until you repair the firearm and have demonstrated that your pistol is safe to shoot.
Enter the ATF, perhaps (in this hypothetical scenario) a spectator at the match. The ATF agent observes the doubling, and confiscates your firearm. He takes it to an ATF lab, which tests it. (According to Horsley, there are not testing standards.) Your gun doubles during the tests.
You are then deemed to be in possession of an unlicensed machine gun. You may be prosecuted, fined, your firearm will almost certainly be confiscated ... and there is no defense.
Nor is there appeal, or oversight.
The engineering definition of 'screw' is "An inclined plane wrapped around a post".
The practical definition of 'screwed' is "The Bureau of Alcohol, Tobacco, Firearms and Explosives".
And until we can convince the American Federal Government to rein in this rogue bureaucracy, we're all screwed.
According to ATF Ruling 2006-2:
The definition of machinegun in the National Firearms Act and the Gun Control Act includes a part or parts that are designed [note #1] and intended for use in converting a weapon into a machinegun. This language includes a device that, when activated by a single pull of the trigger, initiates an automatic firing cycle that continues until the finger is released or the ammunition supply is exhausted.
ATF Rul. 2006-2
The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has been asked by several members of the firearms industry to classify devices that are exclusively designed to increase the rate of fire [note #2] of a semiautomatic firearm. These devices, when attached to a firearm, result in the firearm discharging more than one shot with a single function of the trigger. ATF has been asked whether these devices fall within the definition of machinegun under the National Firearms Act (NFA) and Gun Control Act of 1968 (GCA). As explained herein, these devices, once activated by a single pull of the trigger, initiate an automatic firing cycle which continues until either the finger is released or the ammunition supply is exhausted. Accordingly, these devices are properly classified as a part “designed and intended solely and exclusively, or combination of parts designed and intended, for use in converting a weapon into a machinegun” and therefore machineguns under the NFA and GCA.
The National Firearms Act (NFA), 26 U.S.C. Chapter 53, defines the term “firearm” to include a machinegun. Section 5845(b) of the NFA defines “machinegun” as “any weapon which shoots [note #3], is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger. The term shall also include the frame or receiver of any such weapon, any part designed and intended solely and exclusively, or combination of parts designed and intended [note #4], for use in converting a weapon into a machinegun, and any combination of parts from which a machinegun can be assembled if such parts are in the possession or under the control of a person.” The Gun Control Act of 1968 (GCA), 18 U.S.C. Chapter 44, defines machinegun identically to the NFA. 18 U.S.C. 921(a)(23).
Notes are included by the editor.
"... a part or parts that are designed [note #1] and intended for use in converting a weapon into a machinegun.
"This clause strongly suggests that malfunctioning parts may NOT define a 'machinegun', because they are not 'designed and intended' to '(convert) a weapon into a machinegun'.
This clause also supports the preceding argument. A malfunctioning part should not reasonably be interpreted as being:
' ... exclusively designed to increase the rate of fire [note #2] of a semiautomatic firearm".Note #3:
The referenced phrase is different from the preceding quotes. Where the earlier quotes strongly speak to 'design' and 'intention', this phrase includes the separate clause 'shoots', which can easily be interpreted to include malfunctions.
' ...defines “machinegun” as “any weapon which shoots [note #3], is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger.'That is, whether the subject weapon has been 'designed to shoot' or 'can be readily restored to shoot' in a (full-auto) mode, if it DOES shoot more than one shot per trigger pull, it is a "machinegun" even if you don't want it to so function.
This verbiage is distinctly different from previous (and the following) clauses. We can only assume that this is the unfortunate clumsy verbiage which Michael Sullivan has embraced to justify his arbitrary and unilateral ruling which includes Malfunctions as justification for defining a 'machinegun'.
Again, we see that the rest of the fuling returns to the concept of 'design' and 'intention' in defining a machinegun;
The term shall also include the frame or receiver of any such weapon, any part designed and intended solely and exclusively, or combination of parts designed and intended [note #4], for use in converting a weapon into a machinegun ....